在實際應用中，android2.3的瀏覽器中添加瞭橫豎屏切換的平滑滑動的效果。
Browser的AndroidManifest.xml中
1. <activity android:name="BrowserActivity"
2. android:label="@string/application_name"
3. android:launchMode="singleTask"
4. android:alwaysRetainTaskState="true"
5. android:configChanges="orientation|keyboardHidden"
6. android:theme="@style/BrowserTheme"
7. android:windowSoftInputMode="adjustResize" >
可以看到配置瞭android:configChanges="orientation|keyboardHidden"屬性，而在BrowserActivity的onConfigurationChanged()方法中沒發現有關於頁面重繪的操作。而在framework/base/core/java/android/webkit文件夾中的webview中的
1. protected void onConfigurationChanged (Configuration newConfig) {
2.
3. super.onConfigurationChanged(newConfig);
4.
5. int preRotateWidth;
6. int preRotateHeight;
7.
8. Display display = ((WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
9. preRotateWidth = display.getWidth();
10. preRotateHeight = display.getHeight();
11. int orientation = display.getRotation();
12. orientation = orientation * 90;
13.
14. if (orientation != mOrientation)
15. {
16. float angle = (float)(mOrientation – orientation);
17. if (angle > 180.0f)
18. {
19. angle -= 360.0f;
20. }
21. else if (angle < -180.0f)
22. {
23. angle += 360.0f;
24. }
25. //smooth rotate
26. RotateAnimation anim = new RotateAnimation(angle, TO_DEGREES,
27. Animation.RELATIVE_TO_PARENT, PIVOT_X_VALUE, Animation.RELATIVE_TO_PARENT, PIVOT_Y_VALUE);
28. OvershootInterpolator interp = new OvershootInterpolator(OVERSHOOT_TENSION);
29. anim.setDuration(ANIMATION_DURATION);
30. anim.setFillEnabled(true);
31. anim.initialize(preRotateWidth,preRotateHeight,preRotateWidth,preRotateHeight);
32. anim.setInterpolator(interp);
33. anim.setAnimationListener(new SmoothRotateAnimationListener());
34. ViewParent parent = getParent();
35. // Find the parent view so that, if it is a View class (it can be ViewRoot class), then it's
36. // preferable to start the animation on the parent because the parent View can cache its children
37. // during animation. If Webview has no parent View, then the animation will be done by itself –
38. // meaning that it will have to do the rotation and will be slow.
39. if (parent instanceof View)
40. ((View)parent).startAnimation(anim);
41. else www.aiwalls.com
42. startAnimation(anim);
43. mOrientation = orientation;
44. }
45. }
這個地方完成瞭平滑的實現
摘自：enlife 的BLOG
